Hello,

I configure Hibernate trhough hbm and I have problems loading a collection of strings eagerly:
first my hbm config:


HQL:

- Problem here is a NPE in BasicLoader.isBag(99) due the explicit join of the collection of string <element>s (alias JOINED16) , its an unannotated generated List<String> in my code
- when I remove the join of alias "JOINED16" then each Difference collection is loaded separatly after this oneShotSelect..

env:hibernate 3.2, default-lazy=false

I think there must be an option without java annotation CollectionOfElements( FetchType = Egaer).

ps: the subQuery is needed due possible "Group By Object" in it and missing object expanding... ;)

really Thx for Help & Greats !

Hm.. there are two solutions of joining, My kind of depended joining according to the last joined alias is in this case unsupported.

Only due the use of collection of string the change to explicit non-depended joining is needed here, but may more performant too...

greats

.. dont get it solved.

When I write LEFT JOIN then all works with following loading. When I write LEFT JOIN FETCH the previous described NPE follows :(

I think I have to write WHERE Table.ID = CHidl.ID due this collection of string.. is it so ?

I think now its time for an expert:

Like in this Post it is possible to left join fetch explicit a collection of elements.
http://stackoverflow.com/questions/1093 ... s-elements
I have tried to set @org.hibernate.annotations.CollectionOfElements , even with Fetchtype=EAGER which is already ignored..

I dont understand why this NPE follows when I change LEFT JOIN to LEFT JOIN FETCH
java.lang.NullPointerException
at org.hibernate.loader.BasicLoader.isBag(BasicLoader.java:99)
at org.hibernate.loader.BasicLoader.postInstantiate(BasicLoader.java:78)
at org.hibernate.loader.hql.QueryLoader.<init>(QueryLoader.java:119)
at org.hibernate.hql.ast.QueryTranslatorImpl.doCompile(QueryTranslatorImpl.java:206)
at org.hibernate.hql.ast.QueryTranslatorImpl.compile(QueryTranslatorImpl.java:136)
at org.hibernate.engine.query.HQLQueryPlan.<init>(HQLQueryPlan.java:101)
at org.hibernate.engine.query.HQLQueryPlan.<init>(HQLQueryPlan.java:80)
at org.hibernate.engine.query.QueryPlanCache.getHQLQueryPlan(QueryPlanCache.java:94)
at org.hibernate.impl.AbstractSessionImpl.getHQLQueryPlan(AbstractSessionImpl.java:156)
at org.hibernate.impl.AbstractSessionImpl.createQuery(AbstractSessionImpl.java:135)
at org.hibernate.impl.SessionImpl.createQuery(SessionImpl.java:1651)
at org.hibernate.ejb.AbstractEntityManagerImpl.createQuery(AbstractEntityManagerImpl.java:93)

When I do not join the collection of String and just join its parent with LEFT JOIN FETCH the collection is not loaded in one shot..
When I use the find method then its loaded with one shot for the requested object. I just wanna do what find() does, but in HQL, not with SQL


please Help (dedicated to an expert)

I think I got it now. Only possibility is to enumarte classed in FROM Clause an do in WHere clause: Alias.ObjectID = ChildAlias.ObjectId

corrcted: not possible du reconvertion of the SQL to multiple queries due many-to-one :(/

-> May an expert can put a short stement "not jet possible"...

I think I got it now. Only possibility is to enumarte classed in FROM Clause an do in WHere clause: Alias.ObjectID = ChildAlias.ObjectId

corrcted: not possible because I need Outer Join syntax

The question remains, why comes the NPE ?

I have tried pure @org.hibernate.annotations.CollectionOfElements annotation without Fetchtype without effects.
-> viewtopic.php?t=971700&highlight=onetomany+collectionofelements
The Query Compiler does not recognize "difference" as a bag

Next try was to verify my autodetection properties
before:
persistenceProperties.put("hibernate.archive.autodetection" , "");
persistenceProperties.put("hibernate.ejb.autodetection" , "hbm");
Now:
persistenceProperties.put("hibernate.archive.autodetection" , "");
// persistenceProperties.put("hibernate.ejb.autodetection" , "hbm"); //remarked for class,hbm default
-> NO EFFECTS, NPE remains
-> Dear Experts: Is it nice for u to watch such a MultipleCHoiceThread ? Hoply not...

some additional debug infos:

2009-12-30 20:09:09,744 [DEBUG] org.hibernate.hql.ast.tree.FromReferenceNode - Resolved : DifferencesToPriorStorage_JOINED15 -> difference14_.ObjectId
2009-12-30 20:09:09,745 [DEBUG] org.hibernate.hql.ast.tree.DotNode - getDataType() : Difference -> org.hibernate.type.ListType(yourPackage.DifferencesToPriorStorage.Difference)
2009-12-30 20:09:09,745 [DEBUG] org.hibernate.hql.ast.tree.FromElement - FromClause{level=1} : null (ABSD) -> difference15_
2009-12-30 20:09:09,745 [DEBUG] org.hibernate.hql.ast.tree.FromClause - addCollectionJoinFromElementByPath() : DifferencesToPriorStorage_JOINED15.Difference -> DifferencesToPriorStorage_Difference
2009-12-30 20:09:09,745 [DEBUG] org.hibernate.hql.ast.tree.DotNode - dereferenceCollection() : Created new FROM element for DifferencesToPriorStorage_JOINED15.Difference : DifferencesToPriorStorage_Difference difference15_
2009-12-30 20:09:09,745 [DEBUG] org.hibernate.hql.ast.tree.FromReferenceNode - Resolved : DifferencesToPriorStorage_JOINED15.Difference -> .
2009-12-30 20:09:09,745 [DEBUG] org.hibernate.hql.ast.HqlSqlWalker - createFromJoinElement() : -- join tree --
\-[JOIN_FRAGMENT] FromElement: 'DifferencesToPriorStorage_Difference difference15_' FromElement{explicit,collection join,fetch join,fetch non-lazy properties,classAlias=ABSD,role=yourPackage.DifferencesToPriorStorage.Difference,tableName={none},tableAlias=difference15_,origin=JournalEntry journalent13_,colums={,className=null}}

why is the Type null : "null (ABSD) -> difference15_"

So, I have COllectionOfElements on the List declaration and on its getter method. Hibernate ois configured to look into classed for annortations..

no matter.. i think i will get it next time and iam glad with hibernate and what is running here !
Hibernate makes really Fun and its nice to see what is reached in it.

Wiching u all a Happy new Year !

Andre

I got this error also, and it appears to be a bug in Hibernate up until at least 3.3.2

In org.hibernate.loader.BasicLoader at line 72 there is the following code:

For some reason, one of the values in the collectionPersisters[] is null, which generates a NullPointerException inside isBag:

As seen on line 72, this array of CollectionPersisters is returned by getCollectionPersisters(), which has multiple implementations, and the problem is definitely in one of these implementations, but I didn't have time yet to check where...